Pipe cutter



Patented Nov.. 14, i922. y

.Jorrit J. HARMAN, .or nnwron,.iirlrssaciausiirrs,fiissieiiori,:e 'ssienM-snrs; i. p To oLiiooLciiiYrnu'sr.ooi/irniqmjriausmiin, acoiarona'rionforfi/rassaormsn'r'rs.-

f yfrfrifi cur'rnn.

` A ,application inea iimber 2,1921. siiaiiio-c5iase3.,,gf

Z @ZZ w hom t may cof/120er@ i Be it known that 1,3 oHN J. .fl-Anemia, lof Newton, in the county lof Middlesex' and State of Massachusetts, a citizen vofthe United States, have invented a neii7 `and usefulmpioveinent in Pipe Cutters, ofwhich the following is a'full, clear, andexact description, reference being had to the acconik panying draivings,forniing al part'of this specification, in lexplainingy itsna'turef The present invention relates'to vaniinproveinent in a pipeecutting' tool of thetype employing a number of ypipefcuttler Wheels. Such a pipe cutter fas customarilymade coni-k prises a pair of 'cutterivhfeelsf'andopposing these a single cutter Wheel. rThep'ipe cutter is generally operated bysuccessive backward and forward strokes of a handlecausing the cutter Wheels -by suitable means yof adjust*` ment to engage the pipe',*the Wheels being' occasionally .tightened ontovthe pipe as the Work proceeds.- kThe vWheels duringthe operation tend to 'sever the pipe by displace-1 ment of metal ratherthan by an actualcut# ting ofthe meta-1.? 'The pipe cutter isinef' ficie-nt' in that there visnot `obtanekzl a 'quick initialv tracking of thev cutter Wheels around thefpipe. The 'time "required to sever the pipe is too Vprotracted land'the"operation, re-v quires undue effort onthe part` ofthe ol'oera-y tor. The operationis dfurther inefficientin that it does not result ina completecutting off or severance ofthe pipe, as the single cut-"Iv n ter Wheel Will cut through asec'tionof the pipe ahead of the other cut-ters necessitating they breaking of the unsevered portion ofthe pipe for completing the operatiom'ivliicli *isl sometimes a ydiflicult matter and any event results in leaving an'undesiiable burr. y,

The object of the invention is to overcome the diiiiculties above `pointed' out; I have found that the difficulties,essentially arise from lack of uniformity in the action ofthe cutters, the single'cutter tending to be morei5y active than the other cutters,'and that by`obi taining a proper'unifo'rmity in the action of l the cutters various difficulties heretofore ,enr countered are eliminated 'and the efficiencyV of tlie tool materially increased.

obtained can best be seen and understood by reference to the drawings in 'Which-e Figure l is a side elevation oi a vpipe cut.- ter embodying niy invention.

The manner in which such uniformity is,

larger. angle of convergence, the sides' or y yfaces l5 meeting at'such angle as Will, enable' y Fig; 2 is side elevation rtervvl'ieel of the cutter. n l V i Fig. '3 isa cross section thereof.

'ithr'exsingle Fig. l-jis la Side elevation"of'oneof the" pair ofciitterwheelsQand Fig.' yis cross,sectionthereofl` i y Referring to'jthe draivingsf* y yl represents the curved headior dos? ofthe? `c`utter carrying/a' air Iof-cutter Wheels 2 and 3, respectively.v f flipposing.these vWheels is single cuttery Wheel 4; carri'edby af'blocl slidably arranged up on` a" giiideivayv G'ontlie dog. The several-cutter Wheels are*l arranged to embrace the exterior Asurface"of a pipe ai' 1 i and track around tliefsamein-the.operation of the cuttenf'flhe sliding'lj-loclrandcutter( Wheel carried byitl areniovable"towardforf' f avvay fromI the worlr and tlierebytlie `lsin'gleu cutter Wheel and in factalll the cutter i'iheels' i aretiglitened ontdthepip'e or Work or re# l lea-sed therefroniiin `the operation ofthe cuti" 75 ter.' -Theblockfistmove'dby ascrei'vwhich I passes through and vhas `threaded "connection fg with bosswS on the ydog, `the @inner endof the screiv'being. connected Vto the rear `end oflthe block. The block andcutter Wheelchar'-4 80 ried by itl areinovedjbackwardl andforivardn` relativelyto the pipe or Work` as'thejscreva is turned yin `one directionor "the other. i' ,y The y screw forms aportion ofthe shrank ofalranl dle (not shcvvi) by means ofivliich'the screw'. is"V turned' and byfineans of which, also, ,the cutter Wheels"arenibvedto; engage the *Workv by .backward and :forward strokes of ,they handle. *111' Y l .The cutterlivlieels Zand. 3 turn on `pins liXed in the dog,tlie 4oppersing Wheel "et onza" piniiXed'inthe block.'`

.Each'of the cutter Wheels'comprisesacen; y y. .tialjV or'` hubforming portion lOf'lthrough which the 4pin or sliaftfQ extends. :These laterallyand'diametricallyfoii all the `Wheels.

'Each of the Wheelsisfextended beyond its` liubbya portion llthefopposite 'sidesf'of'f which converge to""`form acutting edgejl K' 'The side-portions or faces 14 ofthe.y Wheels' leading` directly from the4 hubshave pref` erably ya slight'angle of convergencenvhile the side portions'or faces l5 beyond.leading immediately' tothe' cutting edge have 'al the-.edge to 'properly displacethefmetal `ofi e5y y a5` v Ahubs arer'p-referably .of the saine size, both l tool without undue resistance.

the pipe or work during the operation of the An angle of aboutGO degreesA is a lpreferred angle at which the faces meet which lead directly to the cutting edge and these angles are the saine for all vthe wheels. The extent of the i side facesl awa from the cuttin` edfre in f passage through the work than do each of the other cutter wheels, The difference be ltween the surfaces Yl5 `of the ,single cutter ifi/'heel and those of each of the other cutter wheels is so proportioned that the increased' resistance offered the single cutter wheel will just about compensate for the normal undue activity of this cutter over the other cutters, thereby forcing it to operate in unison with tho'other cutters `and enabling all the cutters to break through the work at jthe same vtime and likewisetending to overcome the diifi'- vculties previously referred to.

vThe dimensions of the wheels may vary according to the size of the wheel. and work to be accomplished. ln practice cutter wheels possessing the following dimensions have been found to be very effective for inediuin size work.y @ver all diameter 4of each of the wheels lf@ inches; lateral extent or thickness of hub of each of the wheels .37

of an inch; diameter of hub of each of the .wheelsl of an inch; side faces v14 of all of the wheels incline inwardly at an angle of aboutv l0 degrees g` side faces l5 of all of the wheels meet to form a cutting edge at an angle of degrees; side faces l5 of the single cutter wheels extends ina general direction diametrical to the wheel -OSof an inch. and the corresponding surfaces of each of thtx other wheels extend in like direction .O42 of an inch. These dimensions are illustrative and may 'well ber variedv without departing' from the spirit of the invention.l n

Having thus fully described my invention, I claim and desire to secure by Lettersy Pat.- ent of the United States:-

l. A pipe cutterof the type specied having a pair of cutter wheels and opposing the same a singlel cutter wheel, each of said t wheels having' a cutting edge and surfaces angular to one anothermeeting in saidedge,

ncsa/ie? said surfaces of the single cutter wheel bearing such relation to corresponding` surfaces` of each of the other wheels that the work will offer more resistance to the action of the single cutter wheel than to 'either of the other wheels wherebythe single cutter wheel will function with substantial "uniformity with the other cutter wheels in making a cut in the work as the tool is operated withsuccessive forward and backward strokes."

2. A pipe cutter of the type specified having a pair of cutter wheels and opposing .the same y a single cutter wheel, each of ysaid Wheels havinga "cutting edge and surfaces angular to one another meetingvin said edge, said surfaces of the single ciittei..wheel being longer than corresponding surfaces ofy the other wheels whereby the single cutter wheel will function with substantial. `uniforinity with the other cutter wheels in making a cut in the work. as the tool isoperated with successive forward and backward strokes. l Y l 3. A pipe cutter of the type specified hav-- ing l.a pair of cutter wheels and opposing'the same single cutter wheel, eachl of s id wheels hai/'ing a. cutting edge and surfaces angular to one another meeting in said edge, the angularity between said surfaces being the saine for .all the wheels, the extent of said surfaces for the single cutter wheel being larger than the extent of corresponding surfacesv for each ofthe other wheels whereby the work will'oifer more resistance to the action of the single cutter wheel than to either `of the otherwheels and the single cutter wheelfunction with substantial uniformity with `the other cutter wheels in making a cut in the work as the tool is operated with successive forward and backward strokes.

el. Av pipe `cutter of the type specified havinga pair of cutter wheels` and opposing the saine a single cutter wheel, each ofl said wheels having a ycutting edge and surfaces meeting to form said edge, saidsurfaces of the single cutter wheel being so proper` tioned to the corresponding surfaces of the other wheels that the work will offer suoli resistance to the operation of the single cutW tei' wheel as to cause this wheel rto function with substantial,uniformity with the other cutter wheels ininaking a cut in thework and thereby enable :all lthe cutters to break through'the work at substantially the saine time as the tool is operated with successive forwardv and backward strokes.

JOHN J. HARMAN. 

